In electrical equipment represented by a mobile terminal and the like, an electrical circuit is formed using a printed wiring board. In recent years, there have been higher demands for compactness, lightness, and a variety of shapes of electrical equipment, and these demands have been stronger in the printed wiring board which is one of the component parts.
Regarding a related printed wiring board, there is a technique for curving a printed wiring board according to a curved surface shape as disclosed in Japanese Unexamined Patent Application Publication No. 2007-129039, titled “fluorine resin printed circuit board and manufacturing method thereof” (Patent literature 1), for example. The method of curving the printed wiring board includes a method of applying heat to a printed wiring board formed in a plate shape to curve the printed wiring board, and a method of press-molding the printed wiring board at a high temperature using a curved die.
FIG. 6 is a structural diagram showing a whole structure of a curved printed wiring board according to a related art. The printed wiring board as shown in FIG. 6 is a printed wiring board 21 formed by laminating metal foils 24 and a plurality of layers of prepreg (Prepreg: carbon sheet) 22, and has a curved shape obtained by pressing a prepreg laminated body 23 and metal foils 24 at a high temperature under the vacuum condition using a pair of curved dies.